The invention relates to a circuit for obtaining an accurate replica of an active electrical parameter, i.e. a voltage or a current. The replica is required to be accurate both in respect of magnitude and phase.
In its application to providing a voltage replica, the principal utility of the present invention is to provide an accurate, scaled-down replica of a high voltage. Since such voltage will be used in the precise measurement of power, the phase must also be accurately maintained, or at least the relative phase angle between the input and output must be accurately known.
In its application to providing a current replica, the principal utility of the present invention is to provide an accurate, scaled-up current reference source, preferably in quadrature to the input voltage, for use in the calibration of reactive volt-ampere or volt-ampere-hour meters.
The principal objective of the present invention is to provide increased accuracy over circuits previously available for these purposes.